Stoppable goals correlation with save percentages

Bleedred

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Looking at it now, what you're doing is not so different to what I mention, after all. I think we just have one big difference in how we look at things.
It seems to me that to decide whether a shot is stoppable, you look a lot at its placement the moment it goes into the net. To me, that's not all that relevant, I'm really looking at what's happening on the ice the moment just before the play/shot is made and asking myself, to what extent I would expect a save/goal. I consider how much time/space/position the scorer has, whether the goalie can focus just on him or whether he has to consider passes, whether the goalie is in position (if not, whether it's his fault and whether he can be expected to move quick enough).

I'll try to give you a few arguments, why I use the criteria I use, take them or leave them:
  • Principially, I believe that to compare something across the league, the basic idea should be as high-level and non-arbitrarily as possible. To me, the three categories in my previous post would translate as 1) How often does the goalie screw up? 2) How many goals does he get from 'normal' plays? 3) How many goals does he get when the defense is not there. Sure, the interpretation is still subjective as hell, but, to exaggerate a little, it prevents a goalie falling into one category if he gets more goals through his glove side and another if he gets scored on through stick side.
  • Giving too much importance to the shot placement, you could introduce some kind of bias. When you distinguish between glove/stick, far/short, etc., what if there's a goalie that actually has preferences that you wouldn't expect?
  • The shot placement is likely to even-out throughout the league over the season. If not, perhaps the goalie has some weakness that the opposing teams are exploiting or he has some particular style of positioning. You don't want to filter that out.
  • The on-ice situation is closely related to the team's defense. That is not likely to even out over the year and you do want to filter it out.
  • The on-ice situation is probably easier to assess than shot placement, perhaps making the study more sustainable over the long term?
That being said, I also see why you're doing what you're doing. Perhaps I should just start logging that myself in parallel, once I find some time.

PS: How do you actually store the information, practically? You keep some kind of database? Spreadsheets? You get to download a list of goals somewhere or you're filling in by hand? Also, your experience may vary, but I really prefer to watch the recaps on youtube rather than nhl.com (for me faster loading, better buffering, easier navigation with keyboard arrows...).
I actually have a file on my computer (hope it doesn't croak soon before the season ends, so I probably should periodically copy and paste the updated results in an email to myself) I put down every goalie that has played at least a minute this year and update it every time a new goalie plays a game. And I just put a number next to them and update after each game they play, if they've allowed a goal I considered stoppable.

And I think the biggest difference between myself and others is that I will count a shot against the goalie where he may have been screened, if I feel that he shouldn't have been screened on it. I also give off for simple wrist shots where the goalie is just beaten to the glove, especially to the short side, whereas most say to credit the shooter. And I don't disagree with crediting the shooter in these situations, just that I think the goalie had a good chance at it. Even though it's a more forgivable goal than one goes through the goalie's arm or between his arm and the post, etc. I will also give a stoppable goal on a breakaway (even if it's one where you can't say it's the goalie's fault, just that it's stoppable), if it goes through him or beats him 5-hole, unless he's sliding and is deked and beats him 5-hole, then I don't give him a stoppable goal for getting beaten there. If he's beaten over the glove on a breakaway from close range, I usually count this as a no-chance goal. If it comes from distance and it's over the glove hand, I may count that as a stoppable goal.
 

Bleedred

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To be fair, if the vast majority of HF knew the score, there wouldn't be such a great need for this...

You could assemble a reasonable panel of people that know the game, that would be fine...but opening it up to the "public", as it were, is exactly the opposite of what you want. Sorry to sound like a clown, but that popular vote won't work.
This is why I like former goalie analysts, even if they weren't good goalies when they played, like Brian Boucher. He and I usually seem to see eye to eye on this, as he's usually saying ''That's one the goalie's gotta have'' when the rest of the panel during the intermission is saying ''I can't fault the goalie on any of these''. I remember this happening during the 2017 WCF. When John Gibson got injured and Jonathan Bernier had to play the last couple games. Whatever game Nashville eliminated Anaheim in, Bernier was TERRIBLE. He allowed 4 goals and 3 of them should have been stopped. Boucher was doing that game and pointing out little things that Bernier did wrong, while the NBCSN desk (I remember Keith Jones in particular) was saying ''I don't think it's on Jonathan Bernier here''.

Although, there's two former goalie analysts that I don't like to hear to talk about goalies and goals allowed, and that's Kevin Weekes and Kelly Hrudey. I feel like both are homers. Kevin Weekes called Martin Jones a ''Top-8 guy in the league'' on NHLN about a month ago, despite the fact that he's just average and plays behind a strong team, which fools people into thinking he's a huge part of why that team is strong. I even remember him blowing up Mike Condon a couple years ago. It wasn't when he was a rookie and had that hot start with Montreal, it's since he's been in Ottawa. Hrudey was calling Jake Allen one of the ''Best goalies in the league right now'' about a year ago, which was dumb. And I've also heard him cut goalies a break at other points where they shouldn't have gotten a break. Same with Weekes over on the NHLN in America.
 
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Bleedred

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Honestly, if you just polled HF on every single goal, with a wide agreement on the criteria and consistent voters among every poll, I reckon you'd get some pretty solid results. Obviously that isn't practical but just throwing that out there.
Maybe, but I feel there's a lot of homers out there. I've seen many threads on here where someone is saying ''What happened to (insert goalie)?'' or any player at all, and people will start claiming ''The defense sucks! It's a terrible team! He has no linemates!''.

This gem was last week when Cory Schneider and the Devils played in Detroit. It was Schneider's first game in the NHL this season (he played 3 AHL conditioning games with mediocre results) as he's coming off of surgery from after last season concluded. Now if you don't know yet, Schneider has been a POOR starting goalie since the 16-17 season. He's a .909% goalie over his last 107 NHL games played, which includes his EXCELLENT playoff series against Tampa last year. He has now went 15 consecutive regular season starts of allowing at least 3 goals, which probably hasn't been done by a Devils goalie in over 25 years and hasn't won a regular season game in any of those. Not since December 27th of 2017. So, that's a little backstory on him, if you're not yet familiar with how poor this once elite goalie has been over the last two years. He needs to be bought out after this year, case f***ing closed.



Goals 1 and 3 were stoppable goals. Goal 1 was nasty, it looked like it went off of him and popped up into the back of the net. It was a one timer, but he got so much of this for it to have not been counted as stoppable. Goal 3 wasn't his fault, it was a shorthanded breakaway, but that doesn't mean it wasn't stoppable. Clean wrist shot, gloved it and it fell out for an easy tap in in the blue paint.

Anyway, some on the Devils board were not happy when myself and a few others bitched about him all night. The simple-minded Devils beat writer from the Bergen Record claimed he was a lone bright spot in the loss and whatever dingbat votes in the 3 stars of the game in Detroit gave him the game's third star. Now in my eyes, this was a game where poor goaltending hurts you. You lose the game by one goal and the goalie allows a couple poor ones. This one hurts you a lot more than the blowout losses.
 

Michael Farkas

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This is why I like former goalie analysts, even if they weren't good goalies when they played, like Brian Boucher. He and I usually seem to see eye to eye on this, as he's usually saying ''That's one the goalie's gotta have'' when the rest of the panel during the intermission is saying ''I can't fault the goalie on any of these''. I remember this happening during the 2017 WCF. When John Gibson got injured and Jonathan Bernier had to play the last couple games. Whatever game Nashville eliminated Anaheim in, Bernier was TERRIBLE. He allowed 4 goals and 3 of them should have been stopped. Boucher was doing that game and pointing out little things that Bernier did wrong, while the NBCSN desk (I remember Keith Jones in particular) was saying ''I don't think it's on Jonathan Bernier here''.

Although, there's two former goalie analysts that I don't like to hear to talk about goalies and goals allowed, and that's Kevin Weekes and Kelly Hrudey. I feel like both are homers. Kevin Weekes called Martin Jones a ''Top-8 guy in the league'' on NHLN about a month ago, despite the fact that he's just average and plays behind a strong team, which fools people into thinking he's a huge part of why that team is strong. I even remember him blowing up Mike Condon a couple years ago. It wasn't when he was a rookie and had that hot start with Montreal, it's since he's been in Ottawa. Hrudey was calling Jake Allen one of the ''Best goalies in the league right now'' about a year ago, which was dumb. And I've also heard him cut goalies a break at other points where they shouldn't have gotten a break. Same with Weekes over on the NHLN in America.

This is right.
 
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patnyrnyg

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While I'm on the topic of rebounds, I don't usually count rebound goals as a stoppable goal, unless it's a REALLY bad rebound or if it's a rebound caused by the puck leaking through the goalie or coming out of his glove and laying in the crease and someone putting it in. I did ding James Reimer on a poor rebound a couple weeks ago, where he head butted it right to the guy from the other team and it was put in. If it's a really weak shot and the goalie has it, but drops it, I'll sometimes ding the goalie on that.
So, you would put this one on Price as weak or stoppable as he should have had Staal's initial shot? (Buchnevich's tying goal against Price on Tuesday night)

 

Doctor No

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Interesting analysis - thank you for sharing it, especially here. I've tried to do this before, and have some observations that are at least initial until my toddler determines that I'm in the other room.

Subjectivity is critical here, and personal biases will play into it. If you have a preconceived notion that a goaltender is poor, you'll judge more borderline cases against them. We also don't get clear views of all goals (and so the goals with less useful views will be more inaccurate, perhaps involving highlight bias).

You do also need to look at saves that shouldn't have been saves (I understand the time pressures that you're working under).

Last but not least, here's an interesting look at something Jamie McLennan did similarly when he was a TSN analyst in the 2012 playoffs (and a meta-analysis of that analysis):
Brodeur is a Fraud: The Value of Subjective Evaluation

This is the first thing that came to find when I saw your topic.

The subjectivity bias is something that's going to be exceptionally difficult to overcome; a large sample size of panelists would ameliorate it somewhat but never completely.
 
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Bleedred

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So, you would put this one on Price as weak or stoppable as he should have had Staal's initial shot? (Buchnevich's tying goal against Price on Tuesday night)


Yes. I gave him off for that one. It looked like he gloved it and lost it. There was one other goal I gave him a stoppable goal for during that game, but can’t remember which goal. It was one of the other first couple goals.
 

super6646

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So what are your thoughts on mike smith and the game against Anaheim? There were probably 2 goals he should've had no question.
 

Bleedred

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So what are your thoughts on mike smith and the game against Anaheim? There were probably 2 goals he should've had no question.
Definitely! I gave him for 2 stoppable goals last night. The first one was probably the worst goal we'll scored around the league for the next week and the third goal was not good. If I was really as hard as some claim I am on goalies, I would also ding him on the second goal, as the rebound wasn't that great, but I didn't. By the way, I have Mike Smith tied with Jake Allen for 14 stoppable goals against so far. Both are most likely battling in the league cellar for save percentage among goalies that have played at least 4 or 5 games. There's a couple guys I still have down for 0, but they haven't played a lot of games. Rinne is near the top in save percentage and has allowed 12 goals, and I only have him down for 1 stoppable goal so far.

In that same game, I also gave Ryan Miller a stoppable goal on the second Flames goal. It was a shorthanded one. That was the first goal this season that I've counted as stoppable against Miller.

Out of the 12 goals scored on goalies in last night's games, I gave Smith 2 stoppable's, I gave Miller 1 stoppable and I gave Varlamov 1 stoppable for what I think was the second Predators goal that squeaked through him clean.

Originally I thought the Crosby goal against Holtby should have been nailed as a stoppable one. It was from a really tough angle and got past him just inside the post. After deliberation with myself, I felt I couldn't nail him on that one, as it was a one timer and he still getting over as the shot was coming, which didn't give him a good enough chance to make the save. It was very close though and I could argue he was slow in getting over.
 

Bleedred

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how do you judge what is a stoppable goal and what is not?
Some are goals that most people would agree were poor on the goalie. Something that goes through the pads or the arms/goes through a goalie is most likely gonna be counted as stoppable by me, unless it took a deflection somewhere or it was a one timer or a breakaway and the goalie was either sliding or not able to be in position when the shot was coming at him. A breakaway and wrist shot that goes through the goalie is usually one I'm gonna ding him with for a stoppable goal, unless he's sliding or deked and it beats him through the legs.

I also give off for some wrist shots that beat a goalie glove side, especially short side. These are probably the type of goals that most people would have a problem with me nailing the goalie on. I also don't excuse screens left and right like many posters do and many announcers even do when going over a goal, and highlighting the slightest of screens. That's probably where I'd deviate with the general consensus of people.

I do give more of a break on a shot that goes top shelf stick/blocker side than glove side, unless it comes from a considerable distance. Like the Mark Stone (I think it was?) goal that beat Cory Schneider the other night.

I'm more forgiving of one timers, but I will mark it stoppable if I felt the goalie was in position for it and it squeaks through, or if the goalie should have had enough time to be in position for it.
 

The Macho King

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Finally a big step in the right direction on goalie analytics...bravo.
I like it, but I still feel like it's half of the data I want.

The other half would be some variation of Grade A chances stopped. We're identifying the softies, but we don't quite have the information for the shots that leaves the shooter looking at the ceiling and wondering WTF happened. And I also think Grade A chances are far more contextual than the HDCF/CA analytics (shot location is like... half of what makes a shot dangerous, as you're noting in your stoppable goal numbers).

The downside is this requires a lot more work from you since not all grade A chances are on highlight reels.

Edit: BTW don't know if you (or anyone else) has seen this.

Q&A: Steve Valiquette's radical approach to evaluating shots...

It looks like someone's getting paid a lot of money to do what you're doing here.
 
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Bleedred,
How often are you going to update the league wide chart? And, do you have a quick way to sort it so that only the starting goalies show?

Thanks.
I didn't see the game, so I don't know but what about Dubnyk vs SJS the other night, and vs LAK last night? Where are you posting your daily analysis?
 
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Michael Farkas

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I like it, but I still feel like it's half of the data I want.

The other half would be some variation of Grade A chances stopped. We're identifying the softies, but we don't quite have the information for the shots that leaves the shooter looking at the ceiling and wondering WTF happened. And I also think Grade A chances are far more contextual than the HDCF/CA analytics (shot location is like... half of what makes a shot dangerous, as you're noting in your stoppable goal numbers).

The downside is this requires a lot more work from you since not all grade A chances are on highlight reels.

Edit: BTW don't know if you (or anyone else) has seen this.

Q&A: Steve Valiquette's radical approach to evaluating shots...

It looks like someone's getting paid a lot of money to do what you're doing here.

Yes, very familiar. Was fortunate enough to find out about Valiquette's work before it went fully public...bred from goalie instruction and efficiency...morphed into analytics. Proper order. Don't **** around with numbers that don't affect game play and performance...
 

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Yes, very familiar. Was fortunate enough to find out about Valiquette's work before it went fully public...bred from goalie instruction and efficiency...morphed into analytics. Proper order. Don't **** around with numbers that don't affect game play and performance...

Could you summarize the extent of his analysis for those of us who cannot afford a subscription?
 

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I like that, and I would like to ask bleedred how his evaluation of goals compares with the green/red analysis here.

Thank you.
 

Bleedred

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Bleedred,
How often are you going to update the league wide chart? And, do you have a quick way to sort it so that only the starting goalies show?

Thanks.
I didn't see the game, so I don't know but what about Dubnyk vs SJS the other night, and vs LAK last night? Where are you posting your daily analysis?
I'm posting it on the Devils forum in the out of town scoreboard. https://hfboards.mandatory.com/thre...018-19-part-ii.2556253/page-31#post-151880625

Against the Sharks, I believe I had Dubnyk down for no chance on all 4 goals allowed against San Jose. However, I gave him a stoppable goal on the one he allowed last night to LA.

I can post the updated list and to make it shorter, I will only use the goalies that have started the most games for their team, although there are still some that have almost split it evenly, so I may be off on a few by calling them the ''Starter'' even if they really aren't. I'm just gonna post them in the order that I have them written down in my file. Other than that, there's nothing noteworthy about why they're in this order. The number next to their name is the number of stoppable goals I've counted against them.



Varlamov - 5
Halak - 5 (Rask with 11 stoppable)
Gibson - 7
Dubnyk - 7
Vasilevskiy - 7
Greiss - 5
Rinne - 1
Raanta - 5
Bishop - 10
Andersen - 7
Lundqvist- 8
Price - 11
Howard - 9
Campbell - 7
Markstrom - 9
Hutton - 8
Kinkaid - 9
Crawford - 1 (I'm surprised it's this low, but I can't see too many goals he's had a chance on)
Anderson - 11
Hellebuyck - 10
Talbot - 10
Jones - 8
Fleury - 9
Murray - 7
Elliott - 7
Holtby - 12
Mrazek - 7
Bobrovsky - 8
Reimer - 6
Smith - 14
Allen - 14
 
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Bleedred

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I like that, and I would like to ask bleedred how his evaluation of goals compares with the green/red analysis here.

Thank you.
I'll have to check this out a little later.
 

varano

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Simply incredible. Thank you.

Without sounding like a brat, is it possible to put the percentages next to it too
 
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Bleedred

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Simply incredible. Thank you.

Without sounding like a brat, is it possible to put the percentages next to it too
No problem! Thanks for reading and taking an interest!:nod:

Now, do you mean save percentages? Or stoppable goal percentages, when you ask that I put the percentages next to it?

Since I started this last weekend (I believe it was last Sunday?) I suppose I can update the results again for this Sunday, so I'll do that after I review all of tonight's games, with the updated stoppable goals counts and save percentages.

The only thing is that since it's a lot to type, I will just do this list in the order that I made it and not the order of save percentage or stoppable goals percentage. So, I'll put the updated list in the same order that I put the goalies in on my OP of this thread!
 

Bleedred

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I think I'll hold off until sometime during the day Sunday to post the updated results, including save percentage, as sometimes it takes the whole overnight and until the next morning for save percentages to update on NHL.com and hockey reference.
 

varano

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No problem! Thanks for reading and taking an interest!:nod:

Now, do you mean save percentages? Or stoppable goal percentages, when you ask that I put the percentages next to it?

Since I started this last weekend (I believe it was last Sunday?) I suppose I can update the results again for this Sunday, so I'll do that after I review all of tonight's games, with the updated stoppable goals counts and save percentages.

The only thing is that since it's a lot to type, I will just do this list in the order that I made it and not the order of save percentage or stoppable goals percentage. So, I'll put the updated list in the same order that I put the goalies in on my OP of this thread!
I meant the stoppable goal percentages.
 
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Bleedred

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Updated numbers, as of the conclusion of Saturday's games. The numbers next to each name represent the number of stoppable goals I've counted. The percentage is the percent of stoppable goals allowed. I'm just gonna round off on the percentages. This is in the order of save percentage, as of heading into Sunday's games.

Brossoit: 0
Luongo: 0
Rinne: 1 - 8%
DeSmith: 3 - 23%
Halak: 5 - 29%
Johnson: 2 - 29%
Greiss: 5 - 33%
Miller: 1 - 10%
Rittich: 5 - 39%
Andersen: 7 - 24%
Dubnyk: 7 - 27%
Raanta: 5 - 26%
Gibson: 8 - 21%
Vasilevskiy: 9 - 30%
Varlamov: 6 - 20%
Khudobin: 3 - 25%
Campbell: 7 - 26%
Lehner: 8 - 36%
Lundqvist: 8 - 23%
Howard: 9 - 27%
Ullmark: 5 - 39%
Bishop: 12 - 39%
Koskinen: 4 - 36%
Hutton: 9 - 27%
Nilsson: 5 - 31%
Kuemper: 3 - 18%
Kinkaid: 11 - 26%
Budaj: 0
Elliott: 7 - 23%
Hellebuyck: 11 - 29%
Saros: 6 - 27%
Bobrovsky: 8 - 26%
Stalock: 0
Dell: 3 - 20%
Anderson: 13 - 24%
Darling: 6 - 50%
Holtby: 12 - 32%
Crawford: 1 - 4% (pretty surprised by this)
Rask : 11 - 52%
Talbot: 10 - 29%
Copley: 5 - 42%
Markstrom: 9 - 23%
Georgiev: 4 - 27%
Fleury: 9 - 23%
Niemi: 4 - 24%
Jones: 8 - 24%
Grubauer: 2 - 11%
Price: 11 - 31%
Bernier: 9 - 41%
Ward: 11 - 34%
Murray: 7 - 22%
Domingue: 0
Reimer: 6 - 29%
McElhinney: 4 - 29%
Subban: 2 - 29%
Mrazek: 7 - 32%
Allen: 14 - 34%
Sparks: 5 - 42%
Korpisalo: 3 - 13%
Smith: 14 - 38%
Pickard: 7 - 33%
Schneider: 3 - 38%
Quick: 4 - 24%
Hutchinson: 6 - 43%
McKenna: 4 - 66%
Condon: 3 - 38%
Neuvirth: 1 - 17%

So, one thing I think is safe to say right now, Pekka Rinne has been the best goalie in the league so far. Andersen, Gibson and Varlamov have also been really good.. Vasilevskiy is a weird one. I've noticed in games he's been bad, he's been bad, but in games he's been good, he's been really good. I nailed him for 2 goals last night and in a game about 2-3 weeks ago he allowed 4 poor goals in the game. I forget who that was against. So a couple poor games are skewing those stoppable goal numbers for him. Lehner and Bishop haven't been as good as their save percentages. Neither has Rittich, but it's still be a VERY small sample size.

Crawford, Grabauer, Murray Fleury and Korpisalo haven't been as bad their save percentages. While Price, Holtby and Ward have all been as poor as those save percentages. Holtby has since allowed a stoppable goal in tonight's game, as I've been typing this.

And my eyes and the save percentages can both back up and Allen and Smith, who've both played a very sizable number of games this season, have been the worst goalies in the league.
 
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krutovsdonut

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bleedred, this is an awesome project. thank you for pushing the envelope. not sure i get the summary report of results though. the trouble with the stats as you state them for comparison is that it does not account for other variables (such as goalies who see proportionately more unstoppable goals).

wouldn't it be logical to report a "stoppable shot save percentage" that ignores unstoppable goals either as goals or shots and then restates a save percentage of just the stoppable shots. every goalie's save % then goes up, but some will go up more than others.

would also be very interesting to see how teams stack up on allowing unstoppable goals.
 

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I haven't read this whole thread but have you considered running a regression or some correlation between the numbers to see if more stoppable goals correlate with a lower save percentage?
 

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